Meyer Judgment Sealed

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                  Figure 1 – Existing Site Aerial (sourced from Nearmap)


The existing site drains from south to north as overland sheet flow which is directed towards
the Noosa Drive road reserve. This road reserve consists of a two way road with densely
planted vegetation within the verge on either side of the road. The site ultimately drains to
Noosa River which is located to the north of the site. In the pre-development case no
stormwater from the site discharges to Picture Point Crescent.

Proposed Land Use (Post-development case)

The development proposes a residential subdivision of 1 lot into 2 lots. It is proposed that in
the future a single dwelling will be built on each of the lots. Refer to Appendix A for the proposed
lot reconfiguration layout and indicative building layouts based on the allowable building
footprint.

Stormwater Quantity

The proposed ground areas (including the future driveways) will discharge to the infiltration
trench provided for each lot respectively. The proposed roof drainage pipes will be free draining
and also connect to the infiltration trench. The infiltration trench will allow the stormwater runoff
to discharge into the natural sand as on-site disposal and reduce the overland stormwater
discharge to downstream properties. In addition, the infiltration trench will also act as a
“detention basin” which will attenuate peak stormwater flows. Detention within the trench is
made possible by providing a low-level outlet pipe which will discharge to a headwall with scour
protection and a level spreader (concrete edging). Therefore, the outlet pipe flow will discharge
as sheet flow. In extreme rainfall events, when the infiltration trench reaches its maximum
capacity, any excess stormwater will discharge as sheet flow over the northern boundary due
to the proposed level spreader (concrete edging) which forms part of the infiltration trench.
Note that there is an undeveloped portion of the site that will bypass the infiltration trench




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